Transfusion in Haematological Malignancy and Transplantation

Patients with haematological malignancy and stem cell transplant recipients are heavily transfused, immunosuppressed and at risk of special complications: transfusion associated graft versus host disease, cytomegalovirus infection, alloimmunisation and platelet refractoriness, infection from bacterial contamination, and ABO complications in transplant. Products must be selected carefully, thresholds kept restrictive and the transplant centre's plan followed.

Product requirements. Leucodepleted components for all, irradiated cellular components where indicated (after purine analogues, in Hodgkin lymphoma, and for allogeneic and autologous transplantation), and cytomegalovirus safe components for seronegative recipients.

Risk context. Bleeding from thrombocytopenia and coagulopathy (especially acute promyelocytic leukaemia), anaemia from marrow failure, tumour lysis and hyperleucocytosis, and interference with laboratory tests from treatment.

Special groups. Children, older adults, patients with sepsis, those receiving anti-CD38 therapy, and transplant recipients with ABO mismatch. In East Africa, limited availability of irradiated and cytomegalovirus safe products and platelets means careful use and early planning with the blood bank.

Red cells. Haemoglobin about 7 to 8 g/dL, higher with symptoms, cardiac or pulmonary disease. Do not transfuse red cells to a patient with hyperleucocytosis (white cells over about 100 x 10⁹/L) before cytoreduction unless unavoidable, because increased viscosity can precipitate leukostasis.

Platelets.

• Prophylaxis: under 10 x 10⁹/L in stable patients, and under 20 x 10⁹/L with fever, sepsis, mucositis, coagulopathy or rapid fall.

• Procedures: lumbar puncture under 40 to 50 x 10⁹/L, central venous catheter under 20 x 10⁹/L, and major surgery under 50 x 10⁹/L.

• Active bleeding: keep over 50 x 10⁹/L, over 100 x 10⁹/L in central nervous system bleeding.

• Acute promyelocytic leukaemia: keep platelets over about 30 to 50 x 10⁹/L and fibrinogen over 1.5 g/L until the coagulopathy resolves.

Plasma and cryoprecipitate. For bleeding with coagulopathy, with fibrinogen over 1.5 g/L as the target (higher in acute promyelocytic leukaemia). Not for prophylaxis.

Granulocytes. Rarely used, for life-threatening neutropenic infection unresponsive to therapy, and irradiated.

Transplant considerations.

• ABO mismatch between donor and recipient requires a special transfusion plan from the start of conditioning until the donor red cells have replaced recipient red cells and antibodies have disappeared.

• Red cells: group O during the transition in major or minor mismatch, then the donor group.

• Plasma and platelets: the group that lacks antibodies against both the recipient's and the donor's red cells (AB, or the donor's group in major mismatch, the recipient's group in minor mismatch). The transplant centre sets the final plan.

• Passenger lymphocyte syndrome: haemolysis 5 to 15 days after a minor ABO mismatched transplant, treated with group O red cells and haemolysis monitoring.

Laboratory interference. Anti-CD38 therapy (daratumumab) causes panreactivity in antibody screens and crossmatches, so tell the blood bank before the first dose and take a sample before starting.

Red flags. Fever during transfusion, rash and diarrhoea weeks after transfusion (graft versus host disease), persistent bleeding with normal platelets, and poor platelet increments.

Plan.

1. Document special requirements in the record and on every request (leucodepleted, irradiated, cytomegalovirus safe).

2. Give one unit of red cells at a time, with reassessment, and platelets as one adult dose.

3. Use ABO identical platelets where possible, and check the count 10 minutes to 1 hour after.

4. Treat coagulopathy in acute promyelocytic leukaemia early with platelets, cryoprecipitate or fibrinogen concentrate, plasma and all-trans retinoic acid as the haematologist directs.

5. Test for platelet refractoriness after two poor increments, and use HLA matched platelets where available.

6. Avoid unnecessary transfusion to protect transplant candidates from sensitisation, and avoid blood from relatives who may be donors.

Special groups.

• Children: weight based doses and special products that apply to neonates where relevant.

• Pregnancy: careful matching and early planning.

• Transplant recipients: follow the centre's ABO and special product plan, and check the donor and recipient groups at every request.

Monitoring. Counts before and after platelets, haemoglobin before red cells, fever and rash, fluid balance, ferritin in long term transfusion, and antibody screen at intervals.

Complications. Febrile and allergic reactions, bacterial contamination of platelets, transfusion associated graft versus host disease with unirradiated products, cytomegalovirus infection, alloimmunisation and refractoriness, iron overload, and transplant ABO complications.

Referral and escalation. Haematologist and transplant physician for every complex requirement, and the blood bank for special product orders and ABO plans.

Disposition. Maintain a written record of special requirements and antibodies, and continue them for the duration the haematologist sets (often lifelong for Hodgkin lymphoma and for at least 6 months after allogeneic transplant).